<template>
	<div>
		<router-link tag="div" to="/" class="header-abs"
		v-show="showAbs"
		>
			<div class="iconfont header-abs-back">&#xe624;</div>
		</router-link>
		<div class="header-fixed" v-show="!showAbs"
		:style="opacityStyle"
		>
			<router-link to="/">
				<div class="iconfont header-fixed-back">&#xe624;</div>
			</router-link>
			景点详情
		</div>
	</div>
</template>
<script type="text/javascript">
	export default {
		name: 'DetailHeader',
		data () {
			return {
				showAbs: true,
				opacityStyle: {
					opacity: 0
				}
			}
		},
		methods: {
			handleScroll () {
				const top = document.documentElement.scrollTop
				if (top > 60) {
					let opacity = top / 140
					opacity = opacity > 1 ? 1 : opacity
					this.opacityStyle = { opacity }
					this.showAbs = false
				}else{
					this.showAbs = true
				}
			}
		},
		activated () {
			window.addEventListener('scroll',this.handleScroll)
		},
		deactivated () {
			window.removeEventListener('scroll',this.handleScroll)
		}
	}
</script>

<style lang='stylus' scoped>
	@import '~styles/varibles.styl'
	.header-abs
		position:absolute
		left:.2rem
		top:.2rem
		width:.8rem
		height:.8rem
		line-height:.8rem
		border-radius:.4rem
		text-align:center
		background:rgba(0,0,0,.8)
		.header-abs-back
			color:#fff
			font-size:.4rem
	.header-fixed
		z-index:2
		position:fixed
		top:0
		left:0
		right:0
		line-height:$headerHeight 
		height:$headerHeight
		text-align:center
		color:#fff
		background:$bgColor
		font-size:.32rem
		.header-fixed-back
			position:absolute
			top:0
			left:0
			width:.64rem
			text-align:center
			font-size:.4rem
</style>